Healthcare-associated infections (HAIs) are infections acquired by patients during healthcare treatments for another condition. HAIs in the medical literature are referred to as “nosocomial” infections. HAIs can be deadly, tend to be ubiquitous, and include both bacterial and fungal causes.
Nosocomial infections can cause severe pneumonia and infections of the urinary tract, bloodstream and other parts of the body. Many types are difficult to attack with antibiotics, and their antibiotic resistance is spreading to Gram-negative bacteria that can infect people outside the hospital environment. In the United States, the most frequent type of infection in the hospital context is urinary tract infection (36%), followed by surgical site infection (20%), and then bloodstream infection and pneumonia (both 11%).
Approximately 1 out of every 25 patients hospitalized will contact an HAI. A study conducted in 2011 estimated that there were approximately 722,000 HAIs in U.S. acute care hospitals. About 75,000 hospital patients with HAIs died during their hospitalization and more than half of those patients were treated outside the intensive care unit.
The significant economic consequences of HAIs were published in 1992 based on the Study on the Efficacy of Nosocomial Infection Control (SENIC), a study conducted in the mid-1970s. At the time of publication, the direct cost of HAIs on healthcare was estimated at $6.65 billion (adjusted for inflation). However, recent published evidence puts HAI direct costs today between $28.4 and $33.8 billion dollars. Much of this cost is related to longer patient stays, quarantining parts of the hospital, and discovering and eradicating the source of infection.